Multiple control valve



Sept. 8, 1953 R. |=.V HoDGsoN sfr/LL 2,651,324

MULTIPLE CONTROL vALv'E 3 Shets-Sheet l Filed NOV. l, 1949 5 H l R W TM Nyc 7 [F.M T 5. 5 4 4%., L ILM@ 0 Y .B a .4l 8 2 C C .1. Ll, PLI 2 M 2 w a /c w ,MIN 2 M A w 6 8. 6 6 M/ O m w 5 M @w m Sept. 8, 1953 R. F. HQDGsoN l-:rAL MULTIPLE CONTRQL VALVEl Filed Nov. l. 1949 2 .d G 5 4 J n 1 Fs EPT INVENToRs l E f/oosov l A Byn WML/AM c. @may f Sept. 8,1953 R. F. HoDGsN Erm'. l 2,651,324

MULTIPLE CONTROL VALVE Filed Nov. 1, 1949 Sehens-sheet s Patented Sept. 8, 1953 UNITED sTATEs PATENT OFFICE MULTIPLE CONTROL VALVE Robert F. Hodgson, Chagrin Falls, and William C. Dolch, Willoughby, Ohio, assignors, by mesnev assignments, to The New York Air Brake Company, New York, N. Y., a corporation of New Jersey Application November 1, 1949, Serial No. 124,806 16 Claims. (C1. 137-621) This invention relates to hydraulic power systems and more particularly to valves for controlling the flow of fluid in such systems.

As is Well known, many hydraulic power systems include the following basic elements: a fluid reservoir; a pump to deliver fluid from the reservoir under pressure; a relief valve to pro- -tect the pump against overloads; one or more motors, which in many cases are single-acting or double-acting cylinders; and valve mechanism, usually manually controlled, by which the hydraulic fluid is directed from the pump to the motors and from the motors back to the reservoir, to actuate the motors in one direction or the other.

`Such systems nd important fields of application inthe actuation of machine tools, lift trucks, earth moving and road building machinery, and many other types of machines. In such applications, there are usually a number of elements of the machine which are to be `actuated hydraulically, and therefore there are many systems in use in which a number of motors are operated from a common pump under the control of valves individual to the cylinders.

The valves are, in many cases, housed together at a single point for the convenience of the machine operator. Since the requirements 'of .diverse installations vary with respect to the number of motors to be controlled, as to .whether the motors are single-acting or double-acting, and as to the nature of the control required in such respects as the need to hold the fluid in ,the cylinder in the neutral position of the Valve or the need to float the cylinder when the valve is in neutral position, many different combinations of valves are required.

This invention relates primarily to valves for plural motor systems. A feature of the invention lies in the fact that the multiple valvesare vmade up of individual sections or units, which are interchangeable and may be assembled together in various numbers of various types, By

virtue of this, requirements of great diversity may be satisfied from a relatively small numberof individual components, eliminating the necessity for providing special combinations with the attendant heavy expense of providing patterns and fixtures for the various special combinations. Moreover, a further feature of the invention in this respect lies in the fact that valves which perform different functions are but slightly different in structure so that mass production procedures may be most efciently used. We are aware that sectional valve assemblies vantages of the sectional multiple valve may be' effectively realized.

Multiple valve systems fall generally into one of two classes, those in which the motors are connected to the pump in parallel and those in which the motors are connected in series. Both types have known advantages and disadvantages. The principal limitations of the systems arise in connection with the operation of two or more motors at the same time, which is often highly desirable or essential in practice. With the parallel system, operation of two motors at the same time can only be effected by throttling control of the motors, since if the valves controlling two motors are open full at the same time, the more heavily loaded motor will operate in the reverse direction, discharging into the less heavily loaded motor. While this reverse flow can be prevented by a check valve arrangement, it is still necessary to divide iiow between the motors by throttling the now-to the one offering less resistance to entrance of fluid.

With a series system employing double-acting cylinders, this disadvantage is obviated, since the pump drives the first cylinder in the series and the discharge from this cylinder positively drives the next in series and so on.

However, so far as we are aware, no multiple valve system employing a plurality of valves in a series circuit has been adapted to the control of single-acting cylinders, nor has any .been adapted to the control of groups comprising both single and double-acting cylinders. The system of the invention not only provides for such arrangements, but provides for concurrent power actuation of double-acting cylinders either ahead of or behind the single-acting cylinder when the single-acting cylinder is being exhausted.

We believe the foregoing will -be sufficient to indicate to those skilled in the art the general nature of the invention. A fuller understanding of the principles and advantages thereof may be had from the full description herein of the preferred embodiment of the inven-tion.

The principal object of the invention is to improve the characteristics of, and controlling systems for, multiple motor hydraulic systems. A further object is the provision of a system of valves particularly adaptedfor arrangement in banks and by which multiple valve set-ups adapted to the control of various numbers of motors of different types and ywith different control possibilities may be readily obtained. An additional object of the invention is to provide an improved series circuit for hydraulic power systems, adaptable to .both single-acting and double-acting motors. A still further object ofthe invention is to attain these objects in a system having a very high degree of engineering and economic practicality and acceptability. More specifically, an object of the invention is to provide a multiple valve system in which valves of diverse' characteristics employ structural elements which embody relatively slight modiications from 'each other, so that the system is peculiarly wellad'apted to mass production withconsduent econo- 1 mies. A further object is to utilize the advantages of the hollow plunger and check valve type of valve in a series circuit.

Other objects and advantages of the invention and the manner in which the objects are realized will be clear to those skilled in the art from the appended 'speci'ca'tin 'and the accompanying drawings 4in which; Vl 's-a tra'n'siflese section, t'aken'n aplane containing 'the bent'eilines of the valve plung'ers, of one type of multiple series valveasseniblyin aceodanc vith the invention;

Fig -2 a vievv of a v" IIve section for control of a double'facting'otr, taken n the plane indicatedin -Fig. l; Fig. s isa sectional vi'etv of a valve unit `for control of 'a singlefar'zti`rg motor, taken on a plane 'at fright angles te Fig. 1', and illustrating an alternative "frn of entrol plunger;

Fig. 4 isa' 'sectional view of a "float position 'valve un'ittaken'onlthe planeindic'ated in Fig. l; and

Fig. I5 is asectional view ''f the valve assembly tekenen the 'plane indicated Fig. 1.

The valve" assembly' or Fig. Al iras been @ritsen tive,l 'since it includes three 'difrerent types c con'trlvalvet adapted tciierform differ'- fiit ctrit'rtl "nations 'Itis to te understood,

employed in 'various y'cc'lmbnatit'ins, 'of "type's, 'as vvillfbenad Hear, A The'val've assembly in Fig. rcomprise's 'an inlet section A, a double-acting section B vvith hold positi'i, 'a"single;atirig"sctitn "C, and a 'dubleacting' section D "with float psit'ibrlhseti'on D including also the tttlt iiiaiiifclfl if the valve. 'nie sc tiiijt A 'and 'p 'are constructed with t. piane inner 'tate and the seetins B and c with plane opposedaces'sothatthe sections na'y be nxedttgtnerto ferm a rigid 'andinia-'tight assembly, as vill'be lincre'particularly described. The inlet section A, 'as illustrated in Figs. l and 5, @riferisce a eastttiy, cored to previas an inlet chairib'erll; a `relief 'or exhaustcharnber I2, and an auxiliary chamber I3. The lWall of the body Vitifis*machined plane for junction to the valve A is tapped as indicated at I4 to receive a high pressure fluid inlet which discharges into the chamber II. Section A preferably houses a relief valve I6 to provide a discharge for the pump in the event of overload, although, of course, an external relief valve or a relief valve `in another location could bei/employed. Thereli'ef valve provides a diseharge fromthe 'chamber II` into the chamber I2 upon occurrence of excessive pressure in the inlet chamber. The inner face II of body section B and is formed with outlet passages I8, VllgttridZ freni-'the'chambers I3, Il, and I2, respectively," intliszting the face I1. These passagesaie prvided'n/ith 0-ring seals 22, 23, 24 and 28 fitted in cntrbores or annular grooves in the face Il to prevent escape of hydraulic iiuid T-heivalve sections such as B, C, and D are all so constructed as to fit against the face I1 of the inlet Ysection A and are provided with passages coinciding with the passages Yin the'inlet sect-ion. Similarly each ofthe sections B and A'C isfpi'ovdd With passages to conduct 'fluid lto .flirtlfier "valve units in the' seduence Yso that-these velementsinmay be assembled in concatenation The valvefblo'cl; iB (Figs',` l-a'nd 2) 'is 'adapted for' 'control of 'a doubleiactingl motor, providing forli/ard, r e\'/erse, andfflild positions; The block or-unit B is a generally rectangular 4casting forni'ed v vith tvvo plaire s`ii l l'-fi.c es'l an'd`-2B-, the formero which mafbe allied the iiilet'facethe latter of which the-outlet ace. YA cylin'ci al valve plunger "29 Vis in oiited fforflongitl-'dinal slid'- i'ng "ovement in a 'b'ore 3I\"i'n 'tl'l'e- 'valve bleek. Tapped service ports 32 and 3?v comnnicati'n'g with recesses or "enlargements $4 and V-3'5, *re- 'sp'ectiv'ly, of the valve vciiariirerf y'pr'vii'e Lier-cnne'ction of f th'e "section to'a double7acting-'m'otr- A'passag'e 36 joiningfthe faces jo'f the valve block provides 'a' `-`conduit 'for 'fl discharged by the relief valve throiig'h "p`as`s'f`aige 2l, and for any seepage 'along the` valveplunger. A pa'ssage'S-I at Vthe 'othefend 'of `the valve block, aligned'ftiith passage' I8, 'joins 'the tivo faces, "fprc'l'fi'dil-'ig' l'a -cnd uit fonseepage" 'frorqjfthe other eid of 'the plunger. 'The 'passage 31 enlarged tn prov'ide a rchai-nl)el" t'o Lreceive a centeringfs'pring `-38 'which acts 'in the us'ual' manner tobias the valve plfililr toward its e'utral position. The-'inlet 'faceifitl'e unit vB is fforrned' 'with tvro passages ETSI` registerh the outlets T9 bf the 'inlet chamber, vthese passages terminating 'in "an annular *enlargement d'2 of the valveboie which c'onsti'ttes a lhighress'ur'ef' ifi'ilet forth'e valve 2.9, Annlar rede es 43` and' in 'the valve Chamber '3l re- '.'includes a flange which providingan abutment for the-centering spring 38, the other end of whichk normally abuts a -shoulder 56 on the 38 chamber 31 and the inner face of a cap 51 4screwed into the end. of the valve members. -radial ports The plunger from the chamber 48 registering with the cham- .bers 42 and 43, respectively, neutral position. The chamber provided with radial ports '62 and 64.

reverse connection V ',nletfand outlet occurs. VAs will be apparent,

portions of thepassages 48 vand 49 are bored Out/tb. provide, shoulders 5| constituting' seats urged against the seatsgby compression springs Y53. The inner compression springl a cap 54 threaded into the end of the valve mem- 'berv and tted with a seal 55. The member 54 projects outwardly, thus The spring wall of the valve plunger. also normally abuts the inner body.v The check valve members 52 are formed with radial ports 58 to vent fluid from behind the valve The valve plunger 29 is provided with 59 and 60 outside the check valves.

also has radial V'ports :6| and 63 with the plunger in 49 is similarly A clevis fitting 56 or other suitable tting by which the valve plunger may be reciprocated is threaded into the outer end of the valve plunger and fitted with the seal v61. Since the outer end of the valve plunger is desirably formed longer than rthe inner end, a spacer 68 is preferably tted betweenvvthe outer check valve spring 53 and the ltting '66 so that identical springs may be used for the check valves. A fluid seal and wiper 69 is tted in a counterbore in the valve body to prevent escape of uid along the valve plunger. [The valve bore 31 is additionally recessed as `indi-cated at 1| between the. service chambers and the passages 36 and 31. The recesses 1| are not functional in this particular valve unit, but have been found advantageous in breaking what would otherwisebe a long boreV section without' recesses and which would therevfore be more more resistant to honing or other operations employed in accurately truing and sizing the valve bore. With yall lands short and approximately equal, precise finishing is facill itated.

The operation of the valve section B is as follows: As shown in the drawings, this valve is in neutral position, in which pressure -fluid .flows from the chamber 42 into the succeeding valve section through port 6|, bore 48, port 63,

@chamber 43, and passage 46, and by a parallel '-path, through port 62, bore 49, port 64, chamber 44, and passage 41. The service ports 32 .1 and33 (Fig. 2) are blocked by the valve plunger,

and therefore the motor is held against movement. If the plunger is movedupwardly, as i1- lustrated in Fig. 2, to bring the ports 6I Iand 63 into registry with the chambers 43 and 34 respectively, the ports 62 and 64 into registry with the inlet -chamber 42, and the ports 68 intoregistry with the service passage 35, the motor will vbe .energized to operate in one directionv which may be termed for-ward? Hydraulic iluid then circulates fromv the chamber 42 through ports .g '62 and 64, passage 49, and portsBU, lifting the ycheck valve, into the chamber 35v andv thus to the service port 3'3. Returnfluid from the mo- -tor enters the port 32 and proceeds through chamber 34, port s 63, passage 48, ports 6I, chamber 43,` and passage v4t to theoutlet ofthe section.: When the valveis moveddownwardly, a of the service ports tothe is retained in -the service ports.

vwhen the plunger valve to neutral.

iluid in either case issupplied to the cylinder through one or the other ofthe check valves which are effective to hold uid in thecylinder in the event ofstalling ofthe pump drive motor or other failures in the system. When the motor is operated in either direction,lthe bypass is closed. For example, when the valve is raised, in Fig. 2, the upper vbypass is closed by movement of the ports 6l out of the chamber 42.and the lower bypass is closed by movement of ports 64 out of the chamber 44. A partial or throttling type of control may be executed by movement of the valve member to an intermediate position so as to throttle the bypass and concurrently open the passages to The spring 33 `is compressed between the shoulder 56 and the end cap 51 is moved in one direction and compressed between the ilange of the fitting 54 and the end wall of the chamber 31 when the plunger is moved in the opposite direction, and thus the spring acts to bias the The radial ports in thevalve plunger may be staggered to facilitate throttling of flow.` In this example, the ports -63` and 64 are slightly staggered longitudinally fof. the plunger.

The block B is fitted with O-rngs in thegoutmanner as theunit Al The same is true of the succeeding units.

The valve unit C, for control of. a single-acting cylinder or other motor, utilizes a body which is in most respects identical with that of unit .B and, in fact, the valve Lmit for a doublebut the two views illustrating alternative forms of valve plungers. Those 'parts of the valve casing which are duplicates of those in the double-acting unit are identified by the same reference characters, and, therefore, no extended description of this unit is required. For a singleacting motor, only one service port is required may be eliminated from the a matter of fabrication, lit

and, therefore, one body. However, as

is believed preferable to'plug one of the service ports, for example, service port 32 which is blocked by plug 11. The only other mod ilcation of the valve body lies in providing` an exhaust Vchamber 18 communicating with the outer transverse passage 3'6, which chamber 18 replaces the outermost of the recesses 1I `inthe double-acting valve. As will be apparent, this conversion may be eiected by a simple recessing operation, or'by a modification of the core in casting the valve body. Considering first the plunger 19 illustrated in Fig. 3, this plunger em- -bodiesran end iitting 66, a .centering spring arrangement 38, and an end plugf54v identical to those previously described. The outer end of vBI- which ends vshort ywith a longitudinal bore of theV midpointV of the plunger and communicates with radial ports 64.

the plunger is formed The radial ports 62 of the previous form are omitted. VA check valve member 52 .and spring 453, as previously described, are fitted, the'che'ck lvalve fitting against a shoulder 5| in the passage 8|. Radial ports 68 through the valve plunger on the outerv side of the check valve 19 is solid and correspond to the valve member.

I. pressure would be present in the cylinder in float condition. As a result, if the eifective areas of the two ends of the piston in the cylinder are different, there will be a force tending to move the piston in the cylinder.

Preferably, the sections A and D, which are the end sections of the assembly, are drilled at the corners as indicated at I 06 for mounting bolts to support the assembly.

The manner in which the several sections are held in assembled relation is best shown in Fig. 5. The outlet section D is provided with six drilled andvtapped holes |01 in its mating face which are aligned with holes |08 in the section C. These holes are counterbored at |09 to provide a seat for Allen head machine bolts III which are received in the tapped holes |01 to secure the blocks C and D together. The outer ends of the holes |08 are tapped out as indicated atv I I2 to receive centrally tapped studs IIB which are screwed into place after the bolts III are tightened. The central tapped openings of the studs II3 receive bolts |I4 which secure section B to section C. Section B is drilled, counterbored and tapped in the same manner as section Cv and receives studs IIB on top of the bolts I I4. The section A is drilled at I I1 and counterbored for machine bolts II8 which fix the inlet section to the remainder of the assembly. Obviously, this arrangement may be utilized for as many or as few intermediate sections as are desired, and, since each two adjoining sections are rmly fixed to each other, the arrangement is far superior to conventional tie bolts extending the entire length of the assembly.

As previously stated, the relief valve I6 (Fig. 1) is mounted in the inlet section A. This section is bored through from valve guide and seat member |2I is fitted into the bore |22 between the inlet chamber |I and the relief chamber I2. The valve guide is grooved on its other surface to receive a setscrew |23 which retains it in place. The valve guide is formed with a central bore |24 with lateral openings |25 into the chamber II. A movable relief valve plunger of a diierential type comprises a body |26 which slides in the bore |24 and a head |21 which seals against the open end of the cup |2|. The valve is normally held sealed by a compression spring |28 retained between the valve head and the spring follower |29 adjustably retained by a stud |30, locked in the usual manner by nuts I3I and |32. The adjusting screw |30 is mounted and the spring is guided in a spring retainer |33 threaded into the end of the valve body A. The movable valve member is provided with a central passage I 36 so that the inner end is vented to chamber I2. The bore |24 is stepped so that the effective area of the valve seat |21 is slightly greater than that of the body |26, so that the valve has a differential action and a spring of only moderate strength is required. The passage I4I between the chambers II and I3 and the external opening |42 of the chamber I3 are closed by plugs |43 and |44 end to end anda clear to those skilled in the respectively which may be removed to drive the valve cup from the seat. By a mere reversal of the machining operation, the relief valve can be installed between chambers I I and I3. Y

While the principles of the invention are illustrated in connection wth sectional valves, which have many advantages, particularly in that various numbers of valve units may be assembled as desired, the invention could be incorporated in valves in which a plurality of valve members are incorporated in a single unitary valve block scribed herein. vThis coring would be for the basic double-acting unit with hold position (unit B). Any of these units could be to provide a single-acting unit or a oat" position unit in the manner described above.

Although it seems that the operation of multiple valves according to the invention will be art from the foregoing description of the construction and operation of the various types of sections of which multiple valves are composed, it may be desirable to discuss brieiiy the operation of a multiple valve considering, by way of example, the combination-of Fig. 1 in which the sections in order are: The inlet and relief valve section A; a double-acting hold position section B; a singleacting section C; and a double-acting float position section D. f

Referring to Fig. 1, with all the valves in neutral position as shown, iiuid enters the port |4, passes through chamber II and then through chamber 42, the hollow B is so actuated, incoming fluid fromY the pump is diverted into the cylinder and fiuid exhausted from Vthe cylinder reenters the through passage at 46 or 41. If the other valves are in neutral position the fluid passes freely to the outlet maniflows freely to the exhaust manifold regardless of the setting of the valve D. However, in this position of valve C, the bypass from the inlet passage of unit C to the modied f outlet passage 46" is open; pressure is still supplied Ito-valve unit D. When the unit C issupplying the nsingle-#acting cylinder the .ovv from the pump isall directed-into this cylinder, and there is no supplyy to' succeeding valves in the series, unless a ,throttling-'control is employed in which thesliding valve member 89 'of the unit C is movedonly partially to-the raise portion.

Thevalve unit D'is'the--last of thel series, as illustrated'in Fig; 1, which is desirable because, with the iioat control cylinder the last in the series, there can bel no reaction on thiscylinder in the float position becauseof back pressure fromcylinders iartheralong' in the series. Ofcourse, if the two ends of the'cylinder'controlled bythe valve D arefofequal effective area, or if the effect of back pressure on the cylinder may be tolerated, the float position'valve need Anotbe the'last of 'a series. This valve-'unit canbe employed to supply succeeding cylinders in the same manner as valve-unitB. This isl true because in both the float position and the'operating positions of the valve-huid is `available at'the `outlet of D under pressure, Whether it isbypassed'directly through the unitor is discharged'under pressure from the cylinder controlled bythe unit.

As stated, the particular arrangement of the valveunits illustratedv'in Fig` l is exemplary of various combinationsiofiany number'of unit-sf of anyone or more of the types shown; which combinations can be made to satisfy, different service requirements. In general, it is preferable tov arrange theV double-actingv hold 'position'valvesif any are present, first in the sequence, because these valves always discharge fluid under-A pressure. The same is true oi thefloat position valves, but, in some cases, tosecure a,V completely free float condition, these should be last ina series. Also, it is desirable to putthe singleactingvalves at the end of 'the series because,in the raise operation of the single-acting cylinder; thereis no supplyl offluid'under pressure to the succeeding valves in the series. n

However, except for the case in whichf- `a `singlea acting valve is in some position other `than the the-elast valve-in a ser-ies; all cylinders may be operatedsimultaneously in either direction under full control'.

It will be understood-,- of'fcourse, that for such simultaneous operation the pressure availablein the system must exceedt Ye sum -of the pressure requirements-of thecylinders. This maybe regardedas a disadvantage in comparison to parallel circuit arrangements inv which thef'pressure need'donlybe sufiicient'to actuate theindividual cylinder vvhich'- carries the `heaviest jload. HOW- ever, with series operation a smaller quantity of fluid -is-required, and this compensates for the greater-pressure requirement;v Iny addition, the series Acircuit permits positive i simultaneous opercylinders without the necesheavily heavily loaded cylinders.A

The single-acting` valve of the invention, with a through passage forY pressure fluid inA both neutral and exhaustv positions and af separate return conduit forfluid fexhausted from the cylinder, makes# possible the use of a number of f single-acting valves in a series or the provision of double-actingvvalvessub'- sequent in the series to one or more single-acting valves. If the'single-actingvalve exhausted into the passage-467er 41,* the exhaust fluid from the so that' iluid underv singlef-actinggcylinder might beincapablesoffact# uating cylinders later in the series, sinceltheffluidis not forcedby the positive pump pressure-'fasy it is inthe case ofthe exhaust froma doubleacting cylinder.`

Many modicationsjof structure may befmade Within the scope of the invention; which-isidefi'ned by the appended claims and is notato be regarded as restricted or limited b'y the descrip tion herein of the preferred'embodimentfoftheinvention.

We claim:

l. A multiple control valve-jcomprising-aY plurality of units inconcate'nated relation, each'unit comprising a body with a, valve borethereinfand a plunger reciprocable in thebore-from a neutral position to first and'second operatingi'positions onr opposite sides of the-neutral position, each body dening a service chamber, aninlet conduit, and an outlet conduit, alllintersecting the bore, the inlet and outlet conduits of the successive units denning a-through passage interrupted at the'rvalve bores; the plunger having acential passage with ports extending therefrom atthree longitudianlly spaced points, the rst and second ports registeringv with' thelinlet and outlet conduits'and the third portbeing clcsediby -theebore in neutral position; the iirstf and second-ports being displaced from the outlet'conduit andat least one'of said'ports'registering withth'e" inlet conduit in the first'operating position, th'e'third port registering with the service chamber in the first operating position, and 'the instandsecond ports registeringv with the outlet-'conduit and service chamber inthesecond operating position;

2.' A controlvalve unit comprising a'bodyewitli avalve boreI therein and aiplunger--reeiprocable in the bore from a neutral `positionto rst and second operating positions on' opposite fsides of the neutral position, the body'deningtwor service chambers, an inlet conduit, and an outlet conduit,- all intersecting the bore, the inlet and; outlet con'- duits of the unit defining a. ltlrrrough `passager-in'- terrupted at the valve bore; the plunger'having two central passages with ports extending-from each at three longitudinally spacedpoints; the iirst and second portsregistering With-'the inlet and outlet conduits and the third port"v being closed'by `the borein neutralposition, the first and secondpprts lbeing displaced-from thel outlet conduit and atleast lone'of said ports registering with the inlet conduit Vin the first operating Yposition, the third port registering-with the service chamber in the first operating position, andthe rst and second ports registering with the outlet conduitand service chamber inthev second operating position;

3. A multiple valve for 'controlling a plurality of motors, the valve comprising a Valveunit for each controlled motor,4 the units constitutingl a valve block with-athrough passage for flow of iluidfrom a source of fluid under pressure to a low-pressure discharge; at least two of vsaid units having two motor ports; a` movable valve member in each unit intersecting the-through passage for interconnecting respective motor ports thereof with the sections of the through passage on either side of the valve member; the valve member in each unit which has two motor ports having three positions, in two of which the through'pase sage is interrupted 'and connected with the motor ports in alternative-order, and in'ithethird of which the through passage is open throughthe valve-unit; one of said two motor port 'units having portrmeans serving to' connect' bothzmotor ascii-,324V

passage is open.

4. A multiple valve for controlling a pluralityof motors, the valve comprising a valve unit for each controlled motor, the units constituting a valve block with a through passage for ow of iluid from a source of fluid under pressure to a low-pressure discharge each unit having at least one ,motor port and atleast one unit having two motor ports; 'amovable valve Vmember in each unit intersecting the through passage for interconnecting the motor ports with the through passage; the valve'member in each two motor port unit having three positions, in two of which the through passage is interrupted to form an entrance and an exit connected to the motor ports in alternative order, and in the third of which the through passage is open through the valve unit; the valve member in each unit with one motor port having three positions, in two of which the through Passage is open and in the third of which the through passage is closed and the inflow section thereof is connected with the motor port.V

5. A multiple valve for controlling a plurality of motors, the valve comprising a valve unit for each controlled motor, the units constituting a valve block with a through passage for flow of fluid from a source of iluid under pressure to a low-pressure discharge unithaving at least one motor port and at least one unit having two motor ports; a movable valve member in each unit intersecting the through passage for inter-connecting the motor ports and the through passage; the valve member in each unit with two motor ports having three positionsin two of which the through passage is interrupted to form an entrance and an exit and connected to the motor ports in alternative order, and in one of which the through passage is open through the valve unit, and comprising two check valves in the valve member through which fluid'` is supplied to the motor ports; the valve member in each unit with one motor port having three positions, in two of which the through passage is open and in one of which the through passage is closed and the inow section thereof is connected to the motor port, and comprising a check valve in the valve member through which uid 'is supplied to the motor port.

6. A multiple valve for controlling a plurality of motors, the Vvalve comprising a valve unit for each controlled motor, the units constituting a valve block with a through passage for ow of iluid from a source of fluid under pressure toa low-pressure disch-arge; each unit having at least one motor port and at least oneunit having two motor ports; a movable valve' member in each unit intersecting the throughA passage for inter-L connecting the motor ports and the sections of the through passage on either side of the valve member; the valve member in each unit with two motor ports having three positions, in two of which the through passage is interrupted and connected to the motor ports in alternative order, and in one of which the through passage is open through the valve unit; the valve member in each unit withrone motorport having three positions, in one of which the through passage is open and the motorport is closed, in one of which` the l through passage is closed and the inflow section thereof is connected to the motor port, and in one of which the lthrough passage is closed and the motor portis connected to a low-pressure discharge separate rromthe said through passage.

7. A control valve unit comprising a body with a bore therethrough and a valve member slidable in the bore from a neutral position to either of? being? formed with enlargements providing uid chambers, the

two operating positions, the bore chambers comprising in order longitudinally of the bore a service chamber, an outlet chamber, an inlet chamber, an outletl chamber, anda service chamber, the body having two faces 4formed for assembly to similar valve units'and passages connecting *the inlet and outlet cham-`l similarly-located openings bers, respectively, to on the said faces, respectively, and service ports connected to the service chambers; the valve member being formed with two longitudinal pas, sages and with radial passages from each longis tudinal passage communicating in the neutral:

position of the valve with the inlet and an outlet chamber and with a radial passage from each longitudinal passage communicating with a serv-i ice chamber when the valve is in neutral position passages communicating with the inlet chamber 1n the said one of the operating positions,the two first-mentioned radial passages communi.

eating with the said service and outlet chambers i two operating positions, the bore being: formed with enlargements providing iluid chambers, the chambers comprising in order -longitudinallyl-fof the bore auxiliary chamber means, Ya service chamber, an outlet chamber, an inlet chamber, an outlet chamber, a service chamber, and auxiliary chamber means, the body having two faces formedV for assemblyto similar valve units and passages connecting the inlet and outlet rcham--A bers, respectively, to similarly-located openings on the said faces, respectively, and service vports connected to theservice chambers;` the `valve member being formed with two longitudinal passages and with radial passages from each longitudinal passage communicating in the neutrall position of the valve with the inlet and anoutlet chamber, one of the two iirst-mentioned radial passages communicating with the inlet chamber in the said one of the operating positionsfthe two rst-mentioned radial passages communi-A cating with the said service and outlety chambers in the other said operating position,yand the valve member being formed and with a radial passage from each longitudinal passage com-4 municating with a service chamber when the valve is shifted to one of the operating positions and with the auxiliary chamber means in each of the other two positions. Y

9. A control valve unit comprising abodywith a bore therethrough and a valve member slidable in the bore from a neutral position to either 0f two operating positions, the vbore being formed with enlargements providing fluid chambers, th chambers vcomprising iny order longitudinally of the bore an outlet chamber, Yan inlet chamber, an outlet chamber,` a service chamber, andaJ ref' turn chamber, the body having two faces formed for assembly to similar valve units and passages connecting the inletv and outlet chambers, .ref spectively, to similarly-located openings vonrthe said faces, respectively, and service ports conL nected to the service chambers; the valve mme annees l 5 @ne operaties Petition of the valve With the inlet and-an, outlet chamber and with a second 10nsturlinal passage and withy radial passages theref from communicating with the service .chamber and the return chamber when the valve is shiftedY to the said` one ofV the operating positions, the radial passages co,mrnunicating with theV inlet chamber and the service chamber in the other operating position.

l0. AV control valve unit comprising a, body with a bore therethrough and a valve member slgidablein the bore from a neutral position to eitherof two operating positions, the bore being formed with enlargements providing uid chambers, the chambers comprising in order longitudinally of the bore two auxiliary chambers, a service chamber, an outlet chamber, an inlet chamber, an'outlet chamber, a service chamber, and two auxiliary chambers, the body having a iiuidl inlet connected to the inlet chamber, a fluid outlet connected to the outlet chambers, and service ports for connection to a motor communicating with the service chambers.

l1. A control valve unit comprising a bod;7 with a bore therethrough and a valve member slidable in the bore iroma `neutral position to either of two operating positions, the bore being formed with enlargements providing fluid chambers, the chambers comprising in order longitudinally of the bore a service chamber, an outlet chamber, an inlet chamber, an outletJ chamber, and a service chamber, the body having two faces formed for assembly to similar valve units and passages connecting the inlet and outlet chambers, respectively, to similarly-located openings on the said faces, respectively, and service portsconnected to the service. chambers; the valve member being formed with two longitudinal passages and with radial passages from each communicating in the neutrai position of the valve. with the inlet and an outlet chamber and with aradial passage from. each longitudinal passage communicating with a service chamber when the valve is shifted to one ofthe operating positions, one of the two firstmentioned radial passages communicating wit the inlet chamber in the said one ofthe Operating positions, the two first-mentioned radial passages communicating with the said service an outlet chambers in the other said operating position. n l

l2. A control valve unit comprising a body with a valve bore therein and a plunger reciprocable inthe bore from a neutral position to rst and second-operating positions on opposite sides of the` neutral positie the body defining two service chambers, an inlet conduit. and anoutlet conduit, all intersecting the bore, the inlet and outlet conduits of the unit deiining a through passage interrupted at the valve bore; the plun- 'ger having two central passages with ports extending `from each at three longitudinally spaced points, the first and second ports registering with the inletand outlet conduits and the third port registering with the service port in neutral position, the first and second ports being ldisplaced from the outlet conduit and at least one of said pgrtsvregistering with the inlet conduit in the first operating position, the third port registering withl the service chamber in the first operating position, and the first and second ports registering vvith theoutlet conduit and service chamberin the secoudoperating position.

1 3, A multiple control rality of units in series relation,

valve comprising a plueach unit comq from said series path prisng a `body with a valve bore` therein and ray plunger reciprocable in the bore position to first and second l on opposite sides of the neutral position, each body deiining a service chamber, an inletconduit and an outlet conduit all intersectingI the` bore, the inlet and outlet conduits. of the successive unitsA deiiningV a through pase; sage interrupted at the valve bores; the' plunger having a central passage with pci-tsl extending therefrom. at three longitudinally, spaced points, the first and second ports legSffing with the inlet. and outlet conduits and the,` third port being closed by the bore in neutral position, the rst and second ports being dis; placed from the outlet conduit and at least 0.1i@ of said ports registering with the inlet conduity in the rst operating position, the third portl registering with the service chamber in the first operating position, and the rst and second ports registering with the outlet conduit and servici;` chamberin the second operating position; `and a check valve in the central passage disposed toV block now from the third port to the other potS.

14. A multiple valve for controlling flow of hydraulic fluid to and from a plurality of Vmotors comprising in combination a plurality` of valve' units providing a path forseries now of through the units from a source` to a low-Dijes: sure receiver, at least-one valve unit being dou, ble-acting and adapted to control a double acting motor and at least one unit being singleacting and adaptedto control asingle-acting motor, each unit being constructed to. divert fin@ to the motor it CQQIQls. the double-acting unit beingV constructed to direct exhaust fluid from its motor intoA said pathv for re-use in following units andthe singleacting unit being constructed to direct exhaust d.: fluid directly from the single-acting motor to the receiver while maintaining said series path open to thereby allow either single or simultanetuis operation of the. motors Acontrolled by unitsbotll, ahead of and in back of said singleacting unit when its motor is being exhausted an, k allow exhausting of the single-.actingmotor regard-` less of operating conditions in the. valve units aheadA of or in back of said singlefactng. llnS- 15. A multiple valve for controlling flow ofthy: draulic fluid to and from a plurality of motors' comprising in combination afplurality' of' valve unitsrproviding. a path for flow of ud through the units in series from a sourceV to ,a lOvVrA-Pllisls sure receiver, at least one of the valves'beinga double-acting valve adapted to ,control a double; acting motor and at least one valve beingza single-acting valve adapted to Ycontrol a single!- acting motor; the units being constructed y'to divert fluid from the said path into the'motors controlled thereby; thek double-acting valvesibe; ing constructed to direct fluid returning from the motorscontrolled thereby into the said path and thereby into succeeding valves of the` series through the said path; and the single-acting valves being constructed to direct fluid returning -from the motors controlled thereby into a conduit separate from the said path and discharging into the said receiver. n l 4 4 16. A multiple valve of the open center series connected type comprising a plurality of valve units assembled side byrsideand affording a path yfor fluid flow from a sourcefof iiuid under pres# sure to a low pressure receiver, one of said units being a double-acting valve and yserving'to control a double-acting motor, and the next succeed mg unit being a single acting valve and controlfrom a neutral opnerating positionsling a single acting motor, the double-acting unit having active positions in which it receives iiuid from said path and diverts it to the double-acting motor controlled thereby and simultaneously receives exhaust fluid from that motor and delivers it to said path, and so to the single acting unit, said single acting unit having an auxiliary exhaust through which it may discharge uid returning from its motor.

ROBERT F. HODGSON.

WILLIAM C. DOLCH.

References Cited in the le of this patent UNITED STATES PATENTS 6 Number 

